A compact patch that provides AES and GCM implementations that utilize the
ARMv8 Crypto Extensions. The config flag is MBEDTLS_ARMV8CE_AES_C, which
is disabled by default as we don't do runtime checking for the feature.
The new implementation lives in armv8ce_aes.c.
Provides similar functionality to https://github.com/ARMmbed/mbedtls/pull/432
Thanks to Barry O'Rourke and others for that contribtion.
Tested on a Cortex A53 device and QEMU. On a midrange phone the real AES-GCM
throughput increases about 4x, while raw AES speed is up to 10x faster.
When cross-compiling, you want to set something like:
export CC='aarch64-linux-gnu-gcc'
export CFLAGS='-Ofast -march=armv8-a+crypto'
scripts/config.pl set MBEDTLS_ARMV8CE_AES_C
QEMU seems to also need
export LDFLAGS='-static'
Then run normal make or cmake etc.